//part1:C03:ex3.7.cpp 
//used for statement to replace all with 'X'.
#include <iostream>
#include <string>

int main(void)
{
    using namespace std;
    string s;
    cout << "Enter a string, include space.\n";
    getline(cin, s);
    for (char &c : s)
    {
        c = 'X';
    }
    cout << s << endl;
    
    return 0;
}